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Version 1.0 - First Published 10 July 2000

National Pollutant Inventory

Emission EstimationTechnique Manual

for

Malting Processes

Malting Processes May 2000 i

EMISSION ESTIMATION TECHNIQUESFOR

MALTING PROCESSES

TABLE OF CONTENTS

1.0 INTRODUCTION ....................................................................................................................31.1 Manual Structure .........................................................................................................31.2 Manual Application......................................................................................................4

2.0 PROCESSES AND EMISSIONS ................................................................................................62.1 Process Description...................................................................................................62.2 Emission Sources and Control Technologies .........................................................7

2.2.1 Emissions to Air .........................................................................................72.2.2 Emissions to Water.....................................................................................82.2.3 Emissions to Land ......................................................................................9

3.0 REPORTING THRESHOLDS .................................................................................................103.1 Category 1................................................................................................................103.2 Category 1a..............................................................................................................103.3 Category 2a..............................................................................................................103.4 Category 2b..............................................................................................................103.5 Category 3................................................................................................................10

4.0 REFERENCES ......................................................................................................................11

APPENDIX A - EMISSION ESTIMATION TECHNIQUES ...................................................................12A.1 Direct Measurement ...............................................................................................13

A.1.1 Sampling Data..........................................................................................13A.1.2 Continuous Emission Monitoring System (Cems) Data ..........................15

A.2 Mass Balance ...........................................................................................................18A.3 Engineering Calculations .......................................................................................19

A.3.1 Fuel Analysis ............................................................................................19A.4 Emission Factors .....................................................................................................20

A.4.1 Industry-Wide Emission Factors ..............................................................20A.4.2 Predictive Emission Monitoring (PEM)...................................................21

APPENDIX B - EETS: ACCEPTABLE RELIABILITY AND UNCERTAINTY.......................................23B.1 Direct Measurement ...............................................................................................23B.2 Mass Balance ...........................................................................................................23B.3 Engineering Calculations .......................................................................................23B.4 Emission Factors .....................................................................................................24

APPENDIX C - VARIABLES AND SYMBOLS ....................................................................................25

APPENDIX D - GLOSSARY OF TECHNICAL TERMS AND ABBREVIATIONS....................................26

Malting Processes May 2000 ii

EMISSION ESTIMATION TECHNIQUE MANUAL FOR MALTING PROCESSES

LIST OF FIGURES, TABLES AND EXAMPLES

Figure 1 Scope of the Malting Processes EET Manual and its Relationship withOther EET Manuals.......................................................................................................3

Figure 2 Malthouse Operations: Process Inputs and Emissions ..................................................6

Table 1 Likely Air Emissions dur ing Malting Operations.........................................................8

Table 2 Stack Sample Test Results ..........................................................................................14

Table 3 Example CEMS Output for a Hypothetical Kiln Firing Waste Fuel Oil ....................16

Table 4 Emission Factors for Malt Manufacturing ..................................................................21

Table 5 List of Variables and Symbols ....................................................................................25

Example 1 Using Stack Sampling Data.........................................................................................14

Example 2 Calculating Moisture Percentage ................................................................................15

Example 3 Using CEMS Data.......................................................................................................17

Example 4 Using a Mass Balance .................................................................................................19

Example 5 Using Fuel Analysis Data............................................................................................20

Example 6 Calculating VOC Emissions using an Emission Factor..............................................21

Malting Processes May 2000 3

1.0 IntroductionThe purpose of Emission Estimation Technique (EET) Manuals in this series is to assist Australianmanufacturing, industrial and service facilities to report emissions of listed substances to theNational Pollutant Inventory (NPI). This Manual describes the procedures and recommendedapproaches for estimating emissions from facilities engaged in malting processes.

The malt manufacturing activities covered in this Manual apply to facilities primarily engaged inthe manufacture of malt mainly used as a feed source for the beer brewing industry.

EET MANUAL: Malting Processes

HANDBOOK: Beer and Malt Manufacturing

ANZSIC CODES: 2182

This Manual was drafted by C. M. Dudgeon, on behalf of the NPI Unit of Environment Australia. Ithas been developed through a process of national consultation involving State and Territoryenvironmental authorities and key industry stakeholders.

The scope of this manual is presented diagrammatically in Figure 1.

Malt Processing

'Malting ProcessesEET Manual'

Generic manuals

•'Fuel & Organic Liquid StorageEET Manual'

•'Combustion Engines EET Manual'

•'Combustion in Boilers EETManual'

Transfers(not part of the NPI process)

•Movement of waste between facilities

•Waste disposal to offsite facility

•Movement of material to and from facility

Figure 1 Scope of the Malting Processes EET Manual and its Relationship with Other EETManuals

1.1 Manual Structure

This manual is structured to allow facilities to work through it and address issues in a structured andcoherent manner.

Section 1 Introduction provides general information about this manual.

Section 2 Processes and Emissions discusses likely emissions from facilities andenvironments where emissions may enter.


Section 3 Reporting Thresholds provides a brief overview of each NPI category and givesreporting threshold values for each category.

Section 4 References provides a list of references utilised in the compilation of this Manual.

Appendix A Emission Estimation Techniques addresses the EETs likely to be used by theindustry. This approach has been adopted in order to demonstrate how an EET maybe applied to estimating emissions of a substance and may be supported by otherEETs. For example, some industries and facilities may choose to use a variety ofmass balance approaches to their estimation of specific chemical emissions.However, the mass balance EET is likely to be supported by direct monitoring dataand emission factors.

Appendix B Emission Estimation Techniques: Acceptable Reliability and Uncertaintyaddresses the reliability of each estimation method present in Appendix A.

Appendix C List of Variables and Symbols presents a complete list of variables and symbolsused within this Manual.

Appendix D Glossary gives a glossary of terms and acronyms used in this Manual.

1.2 Manual ApplicationContext and use of the Manual

This NPI manual provides a “how to” guide for the application of various methods to estimateemissions as required by the NPI. It is recognised that the data that is generated in this process willhave varying degrees of accuracy with respect to the actual emissions from malt processingfacilities. In some cases there will necessarily be a large potential error due to inherent assumptionsin the various emissions estimation techniques (EETs) and/or a lack of available information ofchemical processes.

EETs should be considered as ‘points of reference’

The EETs and generic emission factors presented in the manual should be seen as ‘points ofreference’ for guidance purposes only. Each has associated error bands that are potentially quitelarge. Appendix B discusses the general reliability associated with the various methods. Thepotential errors associated with the different EET options should be considered on a case-by-casebasis as to their suitability for a particular facility. Facilities may use EETs that are not outlined inthis document. They must, however, seek the consent of their relevant environmental authority todetermine whether any 'in house’ EETs are suitable for meeting their NPI reporting requirements.


Hierarchical approach recommended in applying EETs

This manual presents a number of different EETs, each of which could be applied to the estimationof NPI substances. The range of available methods should be viewed as a hierarchy of availabletechniques in terms of the error associated with the estimate. Each substance needs to be consideredin terms of the level of error that is acceptable or appropriate with the use of the various estimationtechniques. Also the availability of pre-existing data and the effort required to decrease the errorassociated with the estimate will need to be considered. For example, if emissions of a substanceare clearly very small no matter which EET is applied, then there would be little gained by applyingan EET which required significant additional sampling.

The steps in meeting the reporting requirements of the NPI can be summarised as follows:

• for Category 1 and 1a substances identify which reportable NPI substances are used, producedor stored, if any and determine whether the amounts used or handled are above the “threshold”values and therefore trigger reporting requirements;

• for Category 2a and 2b substances determine the amount and rate of fuel (or waste) burnt eachyear, the annual power consumption and the maximum potential power consumption, and assesswhether the threshold limits are exceeded;

• for Category 3 substances determine the annual emissions to water and assess whether thethreshold limits are exceeded; and

• for those substances above the threshold values, examine the available range of EETs anddetermine emission estimates using the most appropriate EET.

Generally it will be appropriate to consider various EETs as alternative options whose suitabilityshould be evaluated in terms of:

• the associated reliability or error bands; and• the cost/benefit of using a more reliable method.

The accuracy of particular EETs is discussed in Appendix B.

NPI emissions in the environmental context

It should be noted that the NPI reporting process generates emission estimates only. It does notattempt to relate emissions to potential environmental impacts, bioavailability of emissions ornatural background levels.

Facilities may undertake ‘Ancillary Activities’, such as the production of hydrochloric acid orammonium sulfate, either as a process input or through processing of waste streams. Whenestimating emissions a facility should ensure that emissions are not ‘double counted’ (SeeAppendix B) and process maps should be used to minimise the potential for this.


2.0 Processes and EmissionsThe following section presents a brief description of the Malt Manufacturing Industry and identifieslikely sources of emissions.

2.1 Process Description

Malt, primarily barley malt, is the main constituent in the process for beer manufacturing. Maltmanufacturing processes raw barley grain into barley malt utilising five (5) main operations:storage, steeping, germination, kilning and polishing. Figure 2 illustrates typical malthouseoperations with likely emissions points.

Grain Unloading

Grain Storage Silos

Malt Steeping Tanks

Germination

Malt Kiln

Fabric Filter Particulate MatterEmissions

Emissions fromCombustion

VOC Emissions

To Brewing Process

See Beer ManufacturingEET Manual

Figure 2 Malthouse Operations: Process Inputs and Emissions


2.2 Emission Sources and Control Technologies

2.2.1 Emissions to AirAir emissions may be categorised as:Fugitive EmissionsThese are emissions that are not released through a vent or stack. Examples of fugitive emissionsinclude dust from stockpiles, volatilisation of vapour from vats, open vessels or spills, and materialshandling. Emissions emanating from ridgeline roof-vents, louvres, and open doors of a building aswell as equipment leaks, and leaks from valves and flanges are also examples of fugitive emissions.Emission factor EETs are the usual method for determining losses through fugitive emissions.

Fugitive emissions may be present within the malt manufacturing industry. These emissionsgenerally include equipment leaks, emissions from barley and malt transfer operations, windblowndust and of other industrial processes. For guidance on the estimation of emissions from fugitivesources, refer to the Emission Estimation Technique Manual for Fugitive Emissions.Point Source EmissionsThese emissions are exhausted into a vent (excluding roof vents) or stack, and emitted throughpoint sources into the atmosphere. For malt manufacturing operations, main point sources include:

• Emissions from natural gas combustion processes.• Volatile organic compounds (VOCs) such as aldehydes and carboxylic acids.• Particulate emissions from filters and stacks.

Particulate Matter (PM10) emissions from operations such as barley transfer operations and silofilling are NOT reportable under NPI legislation, unless the facility triggers the fuel consumptionthreshold (see Emissions Estimation Technique Manual for Combustion in Boilers). Guidance oncalculating particulate emissions from these operations is given in Section A.4 of this Manual.

A study in Europe (Passant, Richardson, Swannell, Gibson, Woodfield, 1993) indicates thatextremely low concentration VOCs are released during the malting process. A specific example oncalculating this concentration is given in Appendix A.4.1 of this Manual. It is expected that mostmalt manufacturers will have emissions that are below the threshold NPI reporting value (25tonnes) for VOCs.

For guidance on the estimation of emissions from natural gas combustion processes, please refer tothe Emission Estimation Technique Manual for Combustion in Boilers (Section 3.4.2).

Table 1 illustrates likely air emissions from typical Malthouse processes.


Table 1 Likely Air Emissions during Malting Operations

Activity Constituent NPICategory

Comments

MaltingOperations

Volatile Organic Compounds (VOCs) 1a Use Emission Factor

Fuel Burning -Kiln

Carbon MonoxideFluoride CompoundsHydrochloric AcidParticulate Matter (PM10)Polycyclic Aromatic Hydrocarbons (PAHs)Sulfur DioxideTotal Volatile Organic Compounds (VOCs)

2a See EmissionEstimation TechniqueManual for Combustionin Boilers (Section3.4.2)

Fuel Burning -Kiln

Arsenic & compoundsBeryllium & compoundsCadmium & compoundsChromium (III) & CompoundsChromium (VI) & compoundsCopper & compoundsLead & compoundsMagnesium Oxide FumeManganese & compoundsMercury & compoundsNickel & compoundsNickel CarbonylNickel SubsulfidePolychlorinated Dioxins & FuransPLUS all Category 2a substances (above)

2b See EmissionEstimation TechniqueManual for Combustionin Boilers (Section3.4.2)

Grain Storage& TransferOperations

Particulate Matter (PM10) 2a Use Emission Factor

Air emission control technologies, such as electrostatic precipitators, fabric filters or baghouses,and wet scrubbers, are commonly installed to reduce the concentration of substances in venting airstreams prior to emission. Where such emission abatement equipment has been installed, and whereemission factors from uncontrolled sources have been used in emission estimation, the collectionefficiency of the abatement equipment needs to be considered. The NPI substance most commonlyimpacted by this equipment is the PM10 emissions (particulate matter with an equivalentaerodynamic diameter of 10 micrometres or less i.e. ≤10µm). Collection efficiency is different fordifferent substances. Guidance on applying collection efficiencies to emission factor equations isprovided in Appendix B.4.

With regards to emission controls for PM10 emissions in the absence of measured data orknowledge of the collection efficiency for a particular piece of equipment, an efficiency of 90%should be used in the emission factor equation to calculate actual mass emissions. This defaultshould only be used if there is no other available control efficiency with literature or other sources.

2.2.2 Emissions to Water For malt manufacturing operations it is expected that all process liquid effluent and wastewater willbe: • Sent to sewer;• Treated on-site, then sent to sewer;


• Sent offsite for treatment, recycling or recovery; or• Recycled or reused through the process.

Emissions of substances to water which must be reported under NPI legislation can be categorisedas discharges to:

• Surface waters (e.g. lakes, rivers, dams, and estuaries);• Coastal or marine waters; and• Stormwater. Therefore, malt manufacturing facilities are not expected to be required to report for their emissionsto water. However, because of the significant environmental hazards posed by emitting toxicsubstances to water, most facilities emitting NPI-listed substances to waterways are required bytheir relevant State or Territory environment agency to closely monitor and measure theseemissions. Existing sampling data can be used to calculate annual emissions of NPI pollutants.

2.2.3 Emissions to LandEmissions of substances on land within the facility include solid wastes, slurries, sediments, spillsand leaks, storage and distribution of liquids. Such emissions may contain listed substances. Withinthe malting industry it is expected that substances will be either sent to sewer or sent off-site forlandfill, recycling or treatment and in these cases, there is no reporting requirement under NPIlegislation.

Therefore, the only emissions to land which will be reportable are spills and leaks or in the practiceof on-site disposal. Refer to the Emission Estimation Technique Manual for Organic ChemicalProcessing Industries (Sections 9.1 and 9.2) for guidance in estimating releases due to spills/leaksor other releases to groundwater.


3.0 Reporting ThresholdsFor in-depth information of reporting thresholds, refer to The NPI Guide provided within theIndustry Handbook.

3.1 Category 1The Category 1 reporting threshold is triggered if a facility handles, manufactures, imports,processes or uses a total of ten (10) tonnes or more of a Category 1 substance. A complete list ofNPI Category 1 substances are listed in The NPI Guide. With Category 1 substances, a facility isonly required to report those substances that each individually trigger the reporting threshold. It isnot expected that a facility which is only involved in malting processes (and not brewingoperations) will trigger the threshold for any of the Category 1 substances.

3.2 Category 1aThe Category 1a threshold is triggered if the facility either:

• Uses, produces, imports, processes or emits more than 25 tonnes of Volatile OrganicCompounds (VOCs) in a year; or

• Has bulk storage facilities with a design capacity greater than 25 kilotonnes.

3.3 Category 2aBoth Categories 2a and 2b are based on energy consumption or fuel usage. The category 2areporting threshold is triggered if a facility:

• Burns 400 tonnes or more of fuel or waste per year; or• Burns 1 tonne or more of fuel or waste in an hour at any time during the reporting year.

3.4 Category 2bCategory 2b deals with a range of trace metals which are emitted when large quantities of fuel areconsumed. A facility must report emissions under Category 2b if that facility:

• Burns 2 000 tonnes or more of fuel or waste in a year;• Consumes 60 000 megawatt hours of energy in a year; or• If the maximum potential power consumption of the facility at any time in the year is rated at 20

megawatts or more.

3.5 Category 3A facility must report its emissions of Total Nitrogen and/or Total Phosphorus if its annualemissions to water are at, or above:

• 15 tonnes per year for Total Nitrogen (excluding emissions to groundwater and sewer); or• 3 tonnes per year for Total Phosphorus (excluding emissions to groundwater and sewer).


4.0 ReferencesPassant, N., Richardson, S., Swannell, R., Gobson, N., Woodfield, M. (1993) 'Emissions of VolatileOrganic Compounds (VOCs) from the Food and Drink industries of the European Community',Atmospheric Environment, Vol. 27A, No. 16,pp.2555-2566.

US EPA, Compilation of Air Pollutant Emission Factors, Volume I: Stationary Point and AreaSources, AP-42 Section 9.12.1 Malt Beverages, United States Environmental Protection Agency.Accessed online: 3 December 1999 and 4 January 2000,URL: http://www.epa.gov/ttn/chief/ap42pdf/c9s12-1.pdf

US EPA, Compilation of Air Pollutant Emission Factors, Volume I: Stationary Point and AreaSources Backup Documentation, AP-42 Section 9.9.1 Grain Handling, United States EnvironmentalProtection Agency. Accessed online: 23 May 2000,URL: http://www.epa.gov/ttn/chief/fbgdocs/b09s09-1.pdf

The following Emission Estimation Technique Manuals are available at the NPI Homepage(http://www.npi.gov.au), and from your local Environmental ProtectionAuthority:

- Emission Estimation Technique Manual for Combustion in Boilers- Emission Estimation Technique Manual for Fugitive Emissions- Emission Estimation Technique Manual for Organic Chemical Processing Industries


Appendix A - Emission Estimation TechniquesEstimates of emissions of NPI-listed substances to air, water and land should be reported for eachsubstance that triggers a threshold. The reporting list and detailed information on thresholds arecontained in The NPI Guide at the front of this Handbook.

In general, there are four types of emission estimation techniques (EETs) that may be used toestimate emissions from your facility.

The four types described in The NPI Guide are:

• sampling or direct measurement;• mass balance;• fuel analysis or other engineering calculations; and• emission factors.

Select the EET, (or mix of EETs), that is most appropriate for your purposes. For example, youmight choose to use a mass balance to best estimate fugitive losses from pumps and vents, directmeasurement for stack and pipe emissions, and emission factors when estimating losses fromstorage tanks and stockpiles.

If you estimate your emission by using any of these EETs, your data will be displayed on the NPIdatabase as being of ‘acceptable reliability’. Similarly, if your relevant environmental authority hasapproved the use of EETs that are not outlined in this handbook, your data will also be displayed asbeing of ‘acceptable reliability’.

This Manual seeks to provide the most effective emission estimation techniques for the NPIsubstances relevant to this industry. However, the absence of an EET for a substance in thishandbook does not imply that an emission should not be reported to the NPI. The obligation toreport on all relevant emissions remains if reporting thresholds have been exceeded.

You are able to use emission estimation techniques that are not outlined in this manual. Youmust, however, seek the consent of your relevant state or territory environmental authority.For example, if your company has developed site-specific emission factors, you may use theseif approved by your relevant environmental authority.

You should note that the EETs presented in this manual relate principally to average processemissions. Emissions resulting from non-routine events are rarely discussed in the literature, andthere is a general lack of EETs for such events. However, it is important to recognise that emissionsresulting from significant operating excursions and/or accidental situations (e.g. spills) also need tobe estimated. Emissions to land, air and water from spills must be estimated and added to processemissions when calculating total emissions for reporting purposes. The emission resulting from aspill is the net emission, i.e. the quantity of the NPI reportable substance spilled, less the quantityrecovered or consumed during clean up operations.


The usagea of each of the substances listed as Category 1 and 1a under the NPI must be estimatedto determine whether the 10 tonnes (or 25 tonnes for VOCs) reporting threshold is exceeded. If thethreshold is exceeded, emission of these Category 1 and 1a substances must be reported for alloperations/processes relating to the facility, even if the actual emissions of the substances are verylow or zero.aUsage is defined as meaning the handling, manufacture, import, processing, coincidental production or other uses ofthe substances.

A list of the variables and symbols used in this Manual is in Appendix C.

A.1 Direct MeasurementYou may wish to undertake direct measurement in order to report to the NPI, particularly if youalready do so in order to meet other regulatory requirements. However, the NPI does not requireyou to undertake additional sampling and measurement. For the sampling data to be adequate andable to be used for NPI reporting purposes, it would need to be collected over a period of time, andto be representative of operations for the whole reporting period.

A.1.1 Sampling DataStack sampling test reports often provide emissions data in terms of kg per hour or grams per cubicmetre (dry). Annual emissions for NPI reporting can be calculated from this data. Stack tests forNPI reporting should be performed under representative (i.e. normal) operating conditions. Youshould be aware that some tests undertaken for a State or Territory license condition may requirethe test be taken under maximum emissions rating, where emissions are likely to be higher thanwhen operating under normal operating conditions. It may not be valid to use the maximumemission levels to estimate emissions for NPI reporting.

An example of test results is summarised in Table 2. The table shows the results of three differentsampling runs conducted during one test event. The source parameters measured as part of the testrun include gas velocity and moisture content, which are used to determine exhaust gas flow ratesin m3 /s. The filter weight gain is determined gravimetrically and divided by the volume of gassampled, as shown in Equation 1 to determine the PM concentration in grams per m3. Note that thisexample does not present the condensable PM emissions.

Pollutant concentration is then multiplied by the volumetric flow rate to determine the emission ratein kilograms per hour, as shown in Equation 2 and Example 1.

Equation 1

CPM = Cf / Vm, STP

where:

CPM = concentration of PM or gram loading, g/m3

Cf = filter catch, gVm,STP = metered volume of sample at STP, m3

Equation 2

EPM = CPM * Qd * 3.6 * [273 / (273 + T)]

where:


EPM = hourly emissions of PM, kg/hrCPM = concentration of PM or gram loading, g/m3

Qd = stack gas volumetric flow rate, m3/s, dry3.6 = 3600 seconds per hour multiplied by 0.001 kilograms per gram

T = stack gas temperature, °C

Table 2 Stack Sample Test Results

Parameter Symbol Test 1 Test 2 Test 3Total sampling time (sec) 7 200 7 200 7 200Moisture collected (g) gMOIST 395.6 372.6 341.4Filter catch (g) Cf 0.0851 0.0449 0.0625Average sampling rate (m3/s) 1.67 * 10-4 1.67 * 10-4 1.67 * 10-4

Standard metered volume (m3) Vm, STP 1.185 1.160 1.163Volumetric flow rate (m3/s), dry Qd 8.48 8.43 8.45Concentration of particulate (g/m3) CPM 0.0718 0.0387 0.0537Queensland Department of Environment and Heritage 1998

Example 1 Using Stack Sampling Data

Determine the particulate matter emissions from test 1 data in table 2.

From Equation 2 and the stack sampling data for Test 1 in Table 2 with a stack gas temperature of150°C, the PM emissions are estimated as shown below.

CPM = Cf / Vm, STP

= 0.0851 / 1.185= 0.072 g/m3

EPM = CPM * Qd * 3.6 * [273/(273+T)]= 0.072 * 8.48 * 3.6 * [273/(273 + 150)]= 1.42 kg/hr

The information from some stack tests may be reported in grams of particulate per cubic metre ofexhaust gas (wet). UseEquation 3 to calculate particulate emissions in kg/hr on a dry gas basis.

Equation 3EPM = Qw * CPM * 3.6 * (1 - moistR/100) * [273 / (273 + T)]

where:

EPM = hourly emissions of PM in kilograms per hour, kg/hrQw = wet cubic metres of exhaust gas per second, m3/sCPM = concentration of PM or gram loading, g/m3

3.6 = 3600 seconds per hour multiplied by 0.001 kilograms per grammoistR = moisture content, wt%273 = 273 K (0°C)T = stack gas temperature, °C


Total suspended particulates (TSP) are also referred to as total particulate matter (total PM). To determinePM10 from total PM emissions, a size analysis may need to be undertaken. The mass of PM10 fraction canthen be multiplied by the total PM emission rate to produce PM10 emissions. Alternatively, assume that100% of PM emissions are PM10; i.e. assume that all particulate matter emitted to air has an equivalentaerodynamic diameter of 10 micrometres or less i.e. ≤10µm.

To calculate moisture content use Equation 4.

Equation 4

Moisture content = 100 % * weight of water vapour per specificvolume of stack gas divided by total weight of thestack gas in that volume.

( )

( ) ρ STPSTPm

moist

STPm

moist

R

Vg

Vg

moist+

=

,

,

*1000

*1000*%100

where

moistR = moisture content, wt%gmoist = moisture collected, gVm,STP = metered volume of sample at STP, m3

ρSTP = dry density of stack gas sample, kg/m3 at STP (if the density is notknown a default value of 1.62 kg/m3 may be used. This assumes a drygas composition of 50 vol% air and 50 vol% CO2)

Example 2 Calculating Moisture Percentage

A 1.2m3 sample (at STP) of gas contains 410g of water. To calculate the moisture content use Equation 4.

( )

( ) ρSTP

STPm

moist

STPm

moist

R

Vg

Vg

moist+

=

,

,

*1000

*1000*%100

gMOIST/1000 * Vm,STP = 410 / (1000 * 1.2)= 0.342

moistR = 100 * 0.342/(0.342 + 1.62)= 17.4 wt%

A.1.2 Continuous Emission Monitoring System (CEMS) DataA continuous emission monitoring system (CEMS) provides a continuous record of emissions overtime, usually by reporting pollutant concentration. Once the pollutant concentration is known,emission rates are obtained by multiplying the pollutant concentration by the volumetric gas orliquid flow rate of that pollutant.

Although CEMS can report real-time hourly emissions automatically, it may be necessary toestimate annual emissions from hourly concentration data manually. This Section describes how tocalculate emissions for the NPI from CEMS concentration data. The selected CEMS data should be


representative of operating conditions. When possible, data collected over longer periods should beused.

It is important to note that prior to using CEMS to estimate emissions, you should develop aprotocol for collecting and averaging the data in order that the estimate satisfies the localenvironmental authority’s requirement for NPI emission estimations.

To monitor SO2, NOx, VOC, and CO emissions using a CEMS, you use a monitor that measures theconcentration in parts per million by volume dry gas (ppmv d = volume of pollutant gas/106 volumesof dry gas). Flow rates should be measured using a volumetric flow rate monitor. Flow ratesestimated based on heat input using fuel factors may be inaccurate because these systems typicallyrun with high excess air to remove the moisture out of the kiln. Emission rates (kg/hr) are thencalculated by multiplying the stack gas concentrations by the stack gas flow rates.

Table 3 presents example CEM data output over three periods for a hypothetical kiln. The outputincludes pollutant concentrations in parts per million dry basis (ppmvd), diluent (O2 or CO2)concentrations in percent by volume dry basis (%v, d) and gas flow rates; and may include emissionrates in kilograms per hour (kg/hr). This data represents a snapshot of a hypothetical kiln operation.While it is possible to determine total emissions of an individual pollutant over a given time periodfrom this data, assuming the CEM operates properly all year long, an accurate emission estimatecan be made by adding the hourly emission estimates if the CEMS data is representative of typicaloperating conditions.

Table 3 Example CEMS Output for a Hypothetical Kiln Firing Waste Fuel Oil

Time O2Content

Concentration(ppmvd)

GasFlowRate(Q)

Production Rate ofProduct (A)

(vol%)SO2

(ppmvd)NOx

(ppmvd)CO

(ppmvd)VOC

(ppmvd) (m3/s) (tonnes/ hour)1 10.3 150.9 142.9 42.9 554.2 8.52 2902 10.1 144.0 145.7 41.8 582.9 8.48 2933 11.8 123.0 112.7 128.4 515.1 8.85 270

Hourly emissions can be based on concentration measurements as shown in Equation 5.

Equation 5

Ei = (Ci * MWi * Q * 3600) / [22.4 * (T + 273/273) * 106]

where:

Ei = emissions of pollutant i, kg/hrCi = pollutant concentration, ppmv,d

MWi = molecular weight of the pollutant, kg/kg-moleQ = stack gas volumetric flow rate, m3/s3600 = conversion factor, s/hr22.4 = volume occupied by one mole of gas at standard temperature and

pressure (0°C and 101.3 kPa), m3/kg-moleT = stack gas temperature, °C


Actual annual emissions can be calculated by multiplying the emission rate in kg/hr by the numberof actual operating hours per year (OpHrs) as shown in Equation 6 for each typical time period andsumming the results.

Equation 6Ekpy,i = ∑ (Ei * OpHrs)

where:

Ekpy,i = annual emissions of pollutant i, kg/yrEi = emissions of pollutant i, kg/hr (from Equation 5)OpHrs = operating hours, hr/yr

Emissions in kilograms of pollutant per tonne of clinker produced can be calculated by dividing theemission rate in kg/hr by the production rate (tonnes/hr) during the same period from Equation 7.

It should be noted that the emission factor calculated below assumes that the selected time period(i.e. hourly) is representative of annual operating conditions and longer time periods should be usedfor NPI reporting where they are available. Use of the calculation is shown in Example 3.

Equation 7

Ekpt,i = Ei / A

where:

Ekpt,i = emissions of pollutant i per tonne of clinker produced, kg/tEi = hourly emissions of pollutant i, kg/hrA = production rate, t/hr

Example 3 illustrates the application of Equation 5, Equation 6 and Equation 7.

Example 3 Using CEMS Data

This example shows how SO2 emissions can be calculated using Equation 5 based on the CEMSdata for Time Period 1 shown in Table 3, and an exhaust gas temperature of 150°C (423 K).

ESO2,1 = (Ci * MWi * Q * 3600) / [(22.4 * (T + 273/273) * 106]= (150.9 * 64 * 8.52 * 3600) / [22.4 * (423/273) * 106]= 296 217 907 / 34 707 692= 8.53 kg/hr

For Time Period 2, also at 150°C

ESO2,2 = 8.11 kg/hr For Time Period 3, also at 150°C

ESO2,3 = 7.23 kg/hr The duration of periods of representative operating conditions are:

Period 1 = 1 500 hr Period 2 = 2 000 hr Period 3 = 1 800 hr


Total emissions for the year are calculated by adding the results of the three Time Periods usingEquation 6: Ekpy,SO2 = ESO2,1 * OpHrs + ESO2,2 * OpHrs + ESO2,3 * OpHrs

= (8.53 * 1 500) + (8.11 * 2 000) + (7.23 * 1 800) kg = 42 021 kg/yr Emissions, in terms of kg/tonne of product produced when operating in the same mode as TimePeriod 1, can be calculated using Equation 7. Ekpt,SO2 = ESO2 / A = 8.53 / 290 = 2.94 * 10-2 kg SO2 emitted per tonne of product produced When the kiln is operating as in Time Periods 2 or 3, similar calculations can be undertaken foremissions per tonne.

A.2 Mass Balance

A mass balance identifies the quantity of substance going in and out of an entire facility, process, orpiece of equipment. Emissions can be calculated as the difference between input and output of eachlisted substance. Accumulation or depletion of the substance in the facility should also be accountedfor.

A mass balance is based on the following principles:

Equation 8

Overall:

TotalMass

In=

TotalMassOut

+ (Accumulation - Depletion)

Where:

TotalMassOut

=Mass Out in

ProductStreams

+Mass Out

in Waste Streams +MassOut in

Emissions

Equation 9

Component:

TotalComponent

Mass In+

Component MassGenerated =

Component MassConsumed +

TotalComponentMass Out

where:

TotalComponentMass Out

=Component Mass

Out in ProductStream

+Component Mass

Out in WasteStreams

+ComponentMass Out inEmissions


Example 4 illustrates the application of mass balance.

Example 4 Using a Mass Balance

A facility uses 15 tonnes of an NPI -listed substance in one reporting year. It is recorded that 12tonnes of the substance is utilised in the production process. From test data, it is found that 2.5tonnes is sent to sewer via a wastewater stream. None of the substance is accumulated of depleted.To calculate untested stack emissions and fugitive emissions of that product, use Equation 9.

Total Component Mass In + Component Mass Generated = Component Mass Consumed + TotalComponent Mass Out

Total Component Mass Out = Component Mass Out in Product Streams + Component Mass Out inWaste Streams + Component Mass Out in Emissions

where:Total Component Mass In = 15 tonnesComponent Mass Out in Product Streams = 0.0 tonnesComponent Mass Out in Waste Streams = 2.5 tonnesComponent Mass Generated = 0.0 tonnesComponent Mass Consumed = 12 tonnes

Therefore:Component Mass Out in Emission = 15 - 12 - 2.5 tonnes

= 0.5 tonnes

A.3 Engineering CalculationsAn engineering calculation is an estimation method based on physical/chemical properties (e.g.vapour pressure) of the substance and mathematical relationships (e.g. ideal gas law).

A.3.1 Fuel AnalysisFuel analysis is an example of an engineering calculation and can be used to predict SO2, metals,and other emissions based on application of conservation laws, if fuel rate is measured. Thepresence of certain elements in fuels may be used to predict their presence in emission streams.This includes elements such as sulfur that may be converted into other compounds during thecombustion process.

The basic equation used in fuel analysis emission calculations is the following:

Equation 10

Ekpy,i = Qf * Ci,w/100 * (MWi/EWi) * OpHrs

where:

Ekpy,i = annual emissions of pollutant i, kg/yrQf = fuel use, kg/hrOpHrs = operating hours, hr/yrMWi = molecular weight of pollutant emitted, kg/kg-moleEWi = elemental weight of pollutant in fuel, kg/kg-mole


Ci,w = concentration of pollutant i in fuel, weight percent, wt% For instance, SO2 emissions from fuel oil combustion can be calculated based on the concentrationof sulfur in the fuel oil. This approach assumes complete conversion of sulfur to SO2. Therefore, forevery kilogram of sulfur (EW = 32) burned, two kilograms of SO2 (MW = 64) are emitted. Theapplication of this EET is shown in Example 5.

Example 5 Using Fuel Analysis Data

This example shows how SO2 emissions can be calculated from fuel combustion based on fuelanalysis results, and the known fuel flow of the engine. Ekpy,SO2 may be calculated using Equation10 and given the following: Fuel flow (Qf) = 20 900 kg/hr Weight percent sulfur in fuel = 1.17 wt% Operating hours = 1500 hr/yr

Ekpy,SO2 = Qf * Ci/100 * (MWp / EWf) * OpHrs = (20 900) * (1.17/100) * (64 / 32) * 1500 = 733 590 kg/yr

A.4 Emission FactorsAn emission factor is a tool used to estimate emissions to the environment. In this Manual, it relatesthe quantity of substances emitted from a source, to some common activity associated with thoseemissions. Emission factors are obtained from US, European, and Australian sources and areusually expressed as the weight of a substance emitted, divided by the unit weight, volume,distance, or duration of the activity emitting the substance (e.g. kilograms of sulfur dioxide emittedper tonne of air-dried unbleached pulp produced).

Emission factors are used to estimate a facility’s emissions by the general equation:

Equation 11Ekpy,i = A * OpHrs * EFi * [1 - (CEi/100)]

where :

Ekpy,i = emission rate of pollutant i, kg/yrA = production rate, t/hrOpHrs = operating hours, hr/yrEFi = uncontrolled emission factor of pollutant i, kg/tCEi = overall control efficiency of pollutant i, %.

Emission factors developed from measurements for a specific process may sometimes be used toestimate emissions at other sites. Should a company have several processes of similar operation andsize, and emissions are measured from one process source, an emission factor can be developed andapplied to similar sources. It is necessary to have the emission factor reviewed and approved byState or Territory environment agencies prior to its use for NPI estimations.

A.4.1 Industry-Wide Emission Factors


Table 4 includes emission factors for the malt manufacturing industry.

Table 4 Emission Factors for Malt Manufacturing

Substance Emission Factor Emission Factor Code RatingParticulate (PM10) Emissionsfrom Gas-fired Malt Kiln

0.085 kg particulate matteremitted/ tonne barleyb

E

Particulate (PM10) Emissionsfrom Fabric Filter

0.008 kg particulate matteremitted/ tonne barleyb

E

Total Volatile OrganicCompounds (VOCs)

0.6 kg VOCs emitted/ tonnebarleya

E

Source: a Passant, Richardson, Swannell, Gibson & Woodfield, 1993b US EPA, 1998

Estimating VOC Emissions

The methodology for calculating volatile organic compound (VOC) emissions from maltmanufacturing processes is quite straightforward. By multiplying the annual barley (or other inputgrain) tonnage by the emission factor one will arrive at the estimated VOC emissions for maltmanufacturing. Remember, as stated in Passant et.al. (1993 p.2559) this is most likely anoverestimation of VOC emissions, and hence will illustrate the worse case situation.

Equation 12

EVOC = Ain * EFwhere:

EVOC = total emissions of VOCs from malting operations, kg/yrAin = total tonnage of grain used (tonnes/yr)EF = Emission Factor (0.6 kg VOCs/tonne grain)

Example 6 illustrates the use of Equation 12:

Example 6 Calculating VOC Emissions using an Emission Factor

30 000 tonnes of barley are used in a malt manufacturing facility over a reporting year.

Using Equation 12, emissions of Total Volatile Organic compounds can be calculated as follows:

EVOC = Ain * EF

EVOC = 30 000 tonnes/yr * 0.6 kg VOC emitted /tonne= 18 000 kg VOCs/yr

Since 18 000 kg VOCs is below the threshold value of 25 tonnes (25 000 kg), this facility does notneed to report VOCs under Category 1a.

A.4.2 Predictive Emission Monitoring (PEM)


Predictive emission monitoring is based on developing a correlation between pollutant emissionrates and process parameters. A PEM allows facilities to develop site-specific emission factors, oremission factors more relevant to their particular process.

Based on test data, a mathematical correlation can be developed that predicts emissions usingvarious parameters.


Appendix B - EETs: Acceptable Reliability and UncertaintyThis section is intended to give a general overview of some of the inaccuracies associated with eachof the techniques. Although the National Pollutant Inventory does not favour one emissionestimation technique over another, this section does attempt to evaluate the available emissionestimation techniques with regards to accuracy.

Several techniques are available for calculating emissions from Malt Manufacturing facilities. Thetechnique chosen is dependent on available data, and available resources, and the degree ofaccuracy sought by the facility in undertaking the estimate. In general, site-specific data that isrepresentative of normal operations is more accurate than industry-averaged data, such as theemission factors presented in Appendix A of this Manual.

B.1 Direct Measurement

Use of stack and/or workplace health and safety sampling data is likely to be a relatively accuratemethod of estimating air emissions from Malt Manufacturing facilities. However, collection andanalysis of samples from facilities can be very expensive and especially complicated where avariety of NPI-listed substances are emitted, and where most of these emissions are fugitive innature. Sampling data from a specific process may not be representative of the entire manufacturingoperation, and may provide only one example of the facility’s emissions.

To be representative, sampling data used for NPI reporting purposes needs to be collected over anextended period, and to cover all aspects of production.

In the case of CEMS, instrument calibration drift can be problematic and uncaptured data can createlong-term incomplete data sets. However, it may be misleading to assert that a snapshot (stacksampling) can better predict long-term emission characteristics. It is the responsibility of the facilityoperator to properly calibrate and maintain monitoring equipment and the corresponding emissionsdata.

B.2 Mass Balance

Calculating emissions from using a mass balance appears to be a straightforward approach toemission estimation. However, the Malt Manufacturing industry has few substances that lendthemselves to this estimation technique. Also, it is likely that few Australian Malt Manufacturingfacilities consistently track material usage and waste generation with the overall accuracy neededfor application of this method. Inaccuracies associated with individual material tracking, or otheractivities inherent in each material handling stage, can result in large deviations for total facilityemissions. Because emissions from specific materials are typically below 2 percent of grossconsumption, an error of only ± 5 percent in any one step of the operation can significantly skewemission estimations.

B.3 Engineering Calculations

Theoretical and complex equations, or models, can be used for estimating emissions from maltingprocesses.


Use of emission equations to estimate emissions from Malt Manufacturing facilities is a morecomplex and time-consuming process than the use of emission factors. Emission equations requiremore detailed inputs than the use of emission factors but they do provide an emission estimate thatis based on facility-specific conditions

B.4 Emission Factors

Emission factors often have an associated emission factor rating (EFR) code. The EFR is a guide tothe degree of certainty for pollutant emission estimates from an emission factor. This rating systemis common to EETs for many industries and sectors and therefore, to many Industry Handbooks.They are based on rating systems developed by the United States Environmental Protection Agency(US EPA) and the European Environment Agency (EEA). Consequently, the ratings may not bedirectly relevant to Australian industry. Sources for all emission factors cited can be found in thereference section of this document. The emission factor ratings will not form part of the public NPIdatabase.

When using emission factors, you should be aware of the associated EFR code and what that ratingimplies. An A or B rating indicates a greater degree of certainty than a D or E rating. The lesscertainty, the more likely that a given emission factor for a specific source or category is notrepresentative of the source type. These ratings notwithstanding, the main criterion affecting theuncertainty of an emission factor remains the degree of similarity between the equipment/processselected in applying the factor, and the target equipment/process from which the factor was derived.

The EFR system is as follows:

A - ExcellentB - Above AverageC - AverageD - Below AverageE - PoorU - Unrated


Appendix C - Variables and SymbolsTable 5 lists the variables and symbols used throughout this Manual.

Table 5 List of Variables and Symbols

Variable Symbol UnitsAnnual emissions of pollutant i Ekpy,i kg/yrConcentration of PM CPM grams/m3

Concentration of pollutant i by volume Ci ppmvd

Concentration of pollutant i by wt % Ci,w %Dry density of stack gas sample ρSTP kg/m3

Elemental weight of pollutant i EWi kg/kg-moleEmission Factor EF kg/tonneEmissions of pollutant i per tonne of fuelconsumed

Ekpt,i kg/t

Filter Catch Cf gFuel used Qf t/hrGas flow rate Q m3/sHourly emissions of PM EPM kg/hrMetered volume of sample at STP Vm,STPt m3

Moisture collected gMOIST g

Moisture content MOISTR %Molecular weight of pollutant i MWi kg/kg-moleMultiplication sign *Operating hours OpHrs hr/yrOverall control efficiency, (i.e. Emissionreduction control factor)

CEi % reduction in emissions of pollutant i

Production rate A tonnes/hrStandard Temperature & Pressure STP 0oC (273 K) and 1 atmosphere 101.3 kPaTemperature T oCelsiusTotal emissions of pollutant i per hour Ei kg/hrTotal grain input Ain tonnes/yrUncontrolled emission factor for pollutant i EFi kg of pollutant/unit of weight, volume,

distance or duration of activity emitting thepollutant

Volumetric flow rate of stack gas, dry Qd dry cubic metres per second (m3/s)Volumetric flow rate of stack gas, wet Qw wet cubic metres per second (m3/s)


Appendix D - Glossary of Technical Terms and AbbreviationsANZSIC Australian and New Zealand Standard Industrial ClassificationCEMS Continuous Emission Monitoring SystemCO Carbon MonoxideEEA European Environment AgencyEET Emission Estimation TechniqueEFR Code Emission Factor Rating CodeMW Molecular WeightNEPM National Environment Protection MeasureNOx Oxides of NitrogenNPI National Pollutant InventoryO2 OxygenPEM Predictive Emission MonitoringPM Particulate MatterPM10 Particulates which have an aerodynamic diameter equal to or less than 10

micrometers (≤10µm)SO2 sulfur dioxideSTP Standard Temperature and Pressure (0oC (273 K) and 1 atmosphere 101.3 kPa)Transfer Transfers consist of a deposit of a substance into landfill, or discharge of a

substance to a sewer or tailings dam, or removal of a substance from a facility fordestruction, treatment, recycling, reprocessing, recovery or purification (NEPM.Clause 3(3)). Emissions classed as transfers are NOT required to be reportedunder NPI legislation.

TSP Total Suspended ParticulateVOC Volatile Organic Compounds

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